Optical systems of the highest imaging quality require that a plurality of optical lenses, which are mounted in a positionally stable and low stress way, are positioned with respect to one another in the range of a tenth of a micrometer and are connected rigidly together.
In DE 102 59 599 A1, a method is described for the threaded connection of several mounts with optical elements contained in these mounts. Several screws are provided, which are positioned along a circular path and which lie, with their screw heads via flat washers, on a topmost mount of a mount stack. According to the proposed method, regions surrounding the screws are measured using interferometry as reference regions of the mount surfaces after the threaded connection. The torque applied to each screw is varied in such a way that approximately identical interference patterns are produced.
A disadvantage is the high expense in terms of equipment, because mounting a lens always requires an interferometer. Indeed, deformation states in the threaded connection at surrounding areas of the screws can be determined with the interferometric measurements, but the determined interferometric measurement data does not guarantee that these threaded connections have sufficient properties in terms of strength and stability. The measures by which the mutual alignment of the individual optical elements can be guaranteed are impossible to identify.